I was trying to move a "Media Library" for around 2,000 attachments, it led to a big wxr file, around 25 MiB, and as I could import it, the media library always timed out. This made a smaller file (~ 3MiB, which gzipped were around 300 KiB) and thanks to that, I could do it with two tries.

I hope the author keep updating this :)

Note: I exported from a multisite using 3.5.2 and imported using the standard imported into a brande new 3.9.1